The father of a Manhattan fourth grader who yanked his daughter out of school earlier this year because of critical race theory being injected into the curriculum plans to sue the school for defamation after administrators accused him of lying, he said.

Dad Harvey Goldman says his secret weapon in the impending case is a September 2020 Zoom call with Ariela Dubler, who heads the Abraham Heschel School, which he surreptitiously taped.

Heschel administrators falsely accused him of lying about why he pulled his daughter out of the school, and slammed him for claiming other parents, also upset about so-called “antiracist” initiatives, would be taking their kids out as well, claims Goldman, who filed a notice of his intent to sue Thursday in Manhattan Supreme Court.

“Mr. Goldman’s statements about our school are 100 percent false. He is lying. We are not aware of a single family—including his own—who has left our school for reasons he is now claiming. Mr. Goldman’s description of our curriculum, in fourth grade or otherwise, is also fabricated,” the school said told new media in May, when the controversy erupted.

Goldman had already been planning to move to Florida when he took his daughter out of the Upper East Side school, Heschel officials apparently believed.

But in the Sept. 20, 2020 Zoom call, Dubler indicated she knew that Goldman was upset with new anti-racism initiatives at the school, and encouraged him to take his daughter out, since he was unhappy about the curriculum, Goldman told The Post.

“They called me a liar and it’s just not true and luckily I have this tape,” Goldman said.

Calls to the Heschel School, where tuition ranges from $46,000 to more than $51,000 a year, were not returned Friday.

Goldman said first heard of anti-racism initiatives” being planned at the school from an Aug. 2020 newsletter. He argued young kids aren’t capable of understanding “woke” issues — and that it often confuses or troubles them.